Turbine blade pin seal

ABSTRACT

A gas turbine engine turbine disk assembly includes a turbine disk, turbine blades, and pin seals. Each turbine blade includes a platform with a pressure side seal slot extending into a pressure side of the platform and a suction side seal slot extending into a suction side of the platform. The pressure side seal slot and the suction side seal slot are each angled between three and ten degrees in the radial direction relative to the axis of the turbine disk. The pin seal includes a cylindrical shape and is located within a seal slot formed from the pressure side seal slot and the suction side seal slot of adjacent turbine blades.

TECHNICAL FIELD

The present disclosure generally pertains to gas turbine engines, and is more particularly directed toward a turbine blade pin seal.

BACKGROUND

Gas turbine engines include compressor, combustor, and turbine sections. Turbine sections include turbine blades with adjacent slash faces. Heated air or gases from the combustor may pass through a gap between the slash faces, increasing the operating temperature of turbine components.

U.S. Pat. No. 8,137,072 to H. Kim discloses a turbine blade. The turbine blade may have an airfoil extending from a first surface of a turbine platform. The turbine blade may further have a first side pocket of the turbine platform that is configured to substantially entirely house a first moveable seal between a forward wall of the first side pocket and an aft wall of the first side pocket. The first side pocket may have a convex surface, extending between the forward wall and the aft wall, and a concave surface. The turbine blade may also have a second side pocket of the turbine platform configured to receive a portion of a second moveable seal.

The present disclosure is directed toward overcoming one or more of the problems discovered by the inventors.

SUMMARY OF THE DISCLOSURE

A pin seal for a gas turbine engine with a turbine disk and a plurality of turbine blades is disclosed. The pin seal includes a body having a cylindrical shape, a first end, and a second end, opposite and distal to the first end. The pin seal is configured to be installed between two adjacent turbine blades within a pressure side seal slot that extends into a pressure side slash face of a first turbine blade and the suction side seal slot that extends into a suction side slash face of a second turbine blade. The length of the pin seal is configured such that the pin seal extends forward of an airfoil leading edge of each adjacent turbine blade at least by 0.020 inches when the pin seal is in contact with either an aft pressure side surface located at an end of the pressure side seal slot distal to the leading edge of each airfoil or the aft suction side surface located at an end of the suction side seal slot distal to the leading edge of each airfoil. The pin seal is angled from three to ten degrees in a radial direction relative to an axis of the gas turbine engine during operation of the gas turbine engine.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of an exemplary gas turbine engine.

FIG. 2 is a section view of a portion of a turbine disk assembly.

FIG. 3 is a perspective view of the pressure side of a turbine blade of FIG. 2.

FIG. 4 is a perspective view of the suction side of the turbine blade of FIG. 3.

FIG. 5 is a detailed view of the portion of the cross section view of FIG. 2 around pin seal 430.

FIG. 6 is a plan view of the pin seal of FIGS. 2 and 5.

FIG. 7 is the perspective view of the suction side of a turbine blade assembly including the turbine blade of FIG. 4 and the pin seal of FIG. 6.

DETAILED DESCRIPTION

The systems and methods disclosed herein include a turbine disk assembly. In embodiments, the turbine disk assembly includes a turbine disk, turbine blades, and a pin seal. Each turbine blade includes a pressure side seal slot in the pressure side slash face, and a suction side seal slot in the suction side slash face. The pressure side seal slot includes a pressure side sealing surface and the suction side seal slot includes a suction side sealing surface. The pressure side seal slot of a first turbine blade and the suction side seal slot of a second turbine blade, adjacent the first turbine blade, combine to form a seal slot. A pin seal is retained within each seal slot. During operation of the gas turbine engine, each pin seal is located adjacent and in contact with a pressure side sealing surface and a suction side sealing surface. Air or gases heated from the combustion reaction may pass between adjacent pressure side and suction side slash faces. The air may impinge and increase the operating temperature of the disk posts of the turbine disk. The pin seals may block, reduce, or redirect the heated air, which may reduce the operating temperature of the disk posts, increasing the creep life of the turbine disk. The angle between the pressure side sealing surface and the suction side sealing surface may be between ninety-five degrees and one-hundred fifteen degrees, which may reduce possible binding between the pin seal and adjacent turbine blades and facilitate equal distribution of contact loading between the pressure side sealing surface and the suction side sealing surface. The seal slot may be angled in the radial direction relative to the turbine disk axis, which may facilitate lengthening the pin seal, increasing the contact area between the pin seal and both the pressure side sealing surface and the suction side sealing surface.

FIG. 1 is a schematic illustration of an exemplary gas turbine engine. Some of the surfaces have been left out or exaggerated (here and in other figures) for clarity and ease of explanation. Also, the disclosure may reference a forward and an aft direction. Generally, all references to “forward” and “aft” are associated with the flow direction of primary air (i.e., air used in the combustion process), unless specified otherwise. For example, forward is “upstream” relative to primary air flow, and aft is “downstream” relative to primary air flow.

In addition, the disclosure may generally reference a center axis 95 of rotation of the gas turbine engine, which may be generally defined by the longitudinal axis of its shaft 120 (supported by a plurality of bearing assemblies 150). The center axis 95 may be common to or shared with various other engine concentric components. All references to radial, axial, and circumferential directions and measures refer to center axis 95, unless specified otherwise, and terms such as “inner” and “outer” generally indicate a lesser or greater radial distance from, wherein a radial 96 may be in any direction perpendicular and radiating outward from center axis 95.

A gas turbine engine 100 includes an inlet 110, a shaft 120, a gas producer or “compressor” 200, a combustor 300, a turbine 400, an exhaust 500, and a power output coupling 600. The gas turbine engine 100 may have a single shaft or a dual shaft configuration.

The compressor 200 includes a compressor rotor assembly 210, compressor stationary vanes (“stators”) 250, and inlet guide vanes 255. The compressor rotor assembly 210 mechanically couples to shaft 120. As illustrated, the compressor rotor assembly 210 is an axial flow rotor assembly. The compressor rotor assembly 210 includes one or more compressor disk assemblies 220. Each compressor disk assembly 220 includes a compressor rotor disk that is circumferentially populated with compressor rotor blades. Stators 250 axially follow each of the compressor disk assemblies 220. Each compressor disk assembly 220 paired with the adjacent stators 250 that follow the compressor disk assembly 220 is considered a compressor stage. Compressor 200 includes multiple compressor stages. Inlet guide vanes 255 axially precede the first compressor stage.

The combustor 300 includes one or more injectors 350 and includes one or more combustion chambers 390.

The turbine 400 includes a turbine rotor assembly 410, and turbine nozzles 450. The turbine rotor assembly 410 mechanically couples to the shaft 120. As illustrated, the turbine rotor assembly 410 is an axial flow rotor assembly. The turbine rotor assembly 410 includes one or more turbine disk assemblies 420. Each turbine disk assembly 420 includes a turbine disk 422 (shown in FIG. 2) that is circumferentially populated with turbine blades 460 (shown in FIGS. 2-5). Turbine nozzles 450 axially precede each of the turbine disk assemblies 420. Each turbine disk assembly 420 paired with the adjacent turbine nozzles 450 that precede the turbine disk assembly 420 is considered a turbine stage. Turbine 400 includes multiple turbine stages.

The exhaust 500 includes an exhaust diffuser 520 and an exhaust collector 550.

FIG. 2 is a section view of a portion of a turbine disk assembly 420 of the gas turbine engine of FIG. 1. Turbine disk assembly 420 includes a turbine disk 422, turbine blades 460 (two shown in FIG. 2), dampers 425 (one shown in FIG. 2), and pin seals 430 (one shown in FIG. 2). Turbine disk 422 is a cylindrical shape and includes disk posts 424 extending radially outward. Adjacent disk posts 424 form a turbine disk slot 423. Each turbine disk slot 423 may have a fir tree or dovetail shape and is configured to receive a turbine blade 460.

Each turbine blade 460 includes a platform 463, an airfoil 461, and a blade root 462. Airfoil 461 extends outward, in a first direction, from platform 463 forming a leading edge 458 (see FIG. 3), a trailing edge 459 (see FIG. 3), a pressure side 471, and a suction side 481. When turbine blade 460 is installed in turbine disk 422, airfoil 461 extends outward from platform 463. Pressure side 471 spans between leading edge 458 and trailing edge 459 with a concave shape. Suction side 481 is the side opposite pressure side 471 and spans between leading edge 458 and trailing edge 459 with a convex shape.

Blade root 462 extends inward from platform 463, in a second direction, in the direction opposite airfoil 461 or opposite the first direction. When turbine blade 460 is installed in turbine disk 422, blade root 462 extends in the radially inward direction from platform 463. Blade root 462 is the parent component attachment piece and is configured to insert into a turbine disk slot 423. Blade root 462 may have a fir tree or a dovetail shape.

Platform 463 includes a pressure side platform 473 extending out from pressure side 471 and a suction side platform 483 extending out from suction side 481 in the direction opposite pressure side platform 473. When turbine blade 460 is installed in turbine disk 422, pressure side platform 473 extends in a first circumferential direction relative to the axis of turbine disk 422 and suction side platform 483 extends in a second circumferential direction, opposite the first circumferential direction, relative to turbine disk 422.

Pressure side platform 473 includes pressure side slash face 472. Pressure side slash face 472 is the surface at the end of pressure side platform 473 and is distal to airfoil 461. Pressure side slash face 472 may be angled relative to the direction pressure side platform 473 extends. In one embodiment, pressure side slash face 472 is perpendicular to the direction of pressure side platform 473. In another embodiment, pressure side slash face 472 is angled between zero and forty-five degrees from the direction perpendicular to the direction of pressure side platform 473.

Suction side platform 483 includes suction side slash face 482. Suction side slash face 482 is the surface at the end of suction side platform 483 and is distal to airfoil 461. Suction side slash face 482 Suction side slash face 482 may be angled relative to the direction suction side platform 483 extends. In one embodiment, suction side slash face 482 is perpendicular to the direction of suction side platform 483. In another embodiment, suction side slash face 482 is angled between zero and forty-five degrees from the direction perpendicular to the direction of suction side platform 483.

When adjacent turbine blades 460 are installed onto turbine disk 422 the pressure side slash face 472 of a first turbine blade is adjacent to the suction side slash face 482 of a second turbine blade. Pressure side slash face 472 may be parallel to suction side slash face 482. Pressure side slash face 472 of the first turbine blade and suction side slash face 482 of the second turbine blade are configured to form a slash face gap 497 there between.

FIG. 3 is a perspective view of the pressure side 471 of a turbine blade 460 of FIG. 2. Referring to FIG. 3, platform 463 including pressure side platform 473 spans between a forward end 466 and an aft end 467. Leading edge 458 extends out from platform 463 adjacent forward end 466 and trailing edge 459 extends out from platform 463 adjacent aft end 467.

Referring to FIGS. 2 and 3, turbine blade 460 includes forward pressure side damper buttress 476 and aft pressure side damper buttress 477. Forward pressure side damper buttress 476 extends from pressure side platform 473 adjacent the forward end 466 and extends down adjacent blade root 462. Aft pressure side damper buttress 477 extends from pressure side platform 473 adjacent the aft end 467 and extends down adjacent blade root 462.

Pressure side platform 473, forward pressure side damper buttress 476, and aft pressure side damper buttress 477 may be configured to form pressure side underplatform pocket 475. Pressure side platform 473 may include pressure side underplatform surface 498 adjacent pressure side underplatform pocket 475, forward pressure side damper buttress 476 may include forward pressure damper surface 491 adjacent pressure side underplatform pocket 475, and aft pressure side damper buttress 477 may include aft pressure damper surface 492 adjacent pressure side underplatform pocket 475. Aft pressure damper surface 492 may be parallel to forward pressure damper surface 491 and perpendicular to pressure side underplatform surface 498. Aft pressure damper surface 492 faces forward pressure damper surface 491, and forward pressure damper surface 491 faces aft pressure damper surface 492.

FIG. 4 is a perspective view of the suction side 481 of the turbine blade of FIG. 3. Referring to FIG. 4, turbine platform 463 including suction side platform 483 spans between forward end 466 and aft end 467. Referring to FIGS. 2 and 4, turbine blade 460 also includes forward suction side damper buttress 486 and aft suction side damper buttress 487. Forward suction side damper buttress 486 extends from suction side platform 483 adjacent the forward end 466 and extends down adjacent blade root 462. Aft suction side damper buttress 487 extends from suction side platform 483 adjacent the aft end 467 and extends down adjacent blade root 462.

Suction side platform 483, forward suction side damper buttress 486, and aft suction side damper buttress 487 may be configured to form suction side underplatform pocket 485. Suction side platform 483 may include suction side underplatform surface 499 adjacent suction side underplatform pocket 485, forward suction side damper buttress 486 may include forward suction damper surface 493 adjacent suction side underplatform pocket 485, and aft suction side damper buttress 487 may include aft suction damper surface 494 adjacent suction side underplatform pocket 485. Aft suction damper surface 494 may be parallel to forward suction damper surface 493 and perpendicular to suction side underplatform surface 499. Aft suction damper surface 494 faces forward suction damper surface 493, and forward suction damper surface 493 faces aft suction damper surface 494.

Referring to FIG. 2, the damper buttresses including aft pressure side damper buttress 477 and aft suction side damper buttress 487, are configured to hold a damper 425. Each damper 425 is installed radially outward from and adjacent to each disk post 424 between two turbine blades 460 and radially inward from the adjacent pressure side platform 473 and suction side platform 483 of the two turbine blades 460. The pressure side underplatform pocket 475 and the suction side underplatform pocket 485 of adjacent turbine blades 460 are configured to form underplatform pocket 465.

Each turbine blade 460 includes a pressure side seal slot 474 and a suction side seal slot 484. Adjacent turbine blades 460 are also configured to form seal slot 464 with a pressure side seal slot 474 of a first turbine blade and the adjacent suction side seal slot 484 of a second turbine blade. Referring to FIG. 3, pressure side seal slot 474 includes forward pressure side slot 478, aft pressure side slot 479, and pressure side sealing surface 495. Forward pressure side slot 478 extends into pressure side platform 473 from pressure side slash face 472 below the leading edge 458, adjacent to forward pressure side damper buttress 476, and above forward pressure side damper buttress 476. Forward pressure side slot 478 includes forward pressure side surface 441. Forward pressure side surface 441 may have a planar or a rounded surface, and may round into the concave shape of forward pressure side slot 478. Forward pressure side surface 441 is situated forward of leading edge 458, opposite the direction of trailing edge 459, and axially forward of leading edge 458 when turbine blade 460 is installed onto turbine disk 422. Forward pressure side slot 478 may have a concave shape and spans from pressure side underplatform pocket 475 to forward pressure side surface 441, beyond leading edge 458.

Aft pressure side slot 479 extends into pressure side platform 473 from pressure side slash face 472 below the trailing edge 459, adjacent to aft pressure side damper buttress 477, and above aft pressure side damper buttress 477. Aft pressure side slot 479 includes aft pressure side surface 442. Aft pressure side surface 442 is distal to leading edge 458 and is the end surface of pressure side seal slot 474 farthest from leading edge 458. Aft pressure side surface 442 may have a planar or a rounded surface, and may round into the concave shape of aft pressure side slot 479. Aft pressure side slot 479 may have a concave shape and spans from pressure side underplatform pocket 475 to aft pressure side surface 442.

Pressure side sealing surface 495 spans between forward pressure side surface 441 to aft pressure side surface 442, the length of pressure side seal slot 474. Pressure side sealing surface 495 may be a planar surface angling into pressure side platform 473 from pressure side slash face 472. Forward pressure side slot 478 may include the forward portion of pressure side sealing surface 495. Aft pressure side slot 479 may include the aft portion of pressure side sealing surface 495. The portion of pressure side sealing surface 495 between forward pressure side slot 478 and aft pressure side slot 479 may angle into pressure side platform 473 to pressure side underplatform pocket 475.

Pressure side seal slot 474 may span along pressure side slash face 472 at an angle with forward pressure side slot 478 angled toward forward end 466 and in the direction that blade root 462 extends from platform 463, and with aft pressure side slot 479 angled toward aft end 467 and in the direction that airfoil 461 extends from platform 463. Pressure side seal slot 474 may be angled relative to a reference axis. The reference axis is coaxial to the axis of turbine disk 422 when turbine blade 460 is installed onto turbine disk 422 and is coaxial to center axis 95 (shown in FIG. 1), the centerline of gas turbine engine 100, when turbine blade 460 is installed within gas turbine engine 100. The description with regard to the reference axis applies to the axis of turbine disk 422 when turbine blade 460 is installed onto turbine disk 422 and to center axis 95 when turbine blade 460 is installed within gas turbine engine 100. The reference axis includes a forward direction extending toward compressor 200 when turbine blade 460 is installed within gas turbine engine 100 and an aft direction extending away from compressor 200 when turbine blade 460 is installed within gas turbine engine 100.

Pressure side seal slot 474 may be angled in the radial direction relative to the reference axis with forward pressure side slot 478 being closer to the reference axis than aft pressure side slot 479. Angle 87 is the angle of pressure side seal slot 474 relative to the reference axis. Reference line 85 is shown to illustrate angle 87. Reference line 85 is parallel to the reference axis and is shifted radially outward from the reference axis. In one embodiment, pressure side seal slot 474 is angled relative to the reference axis in the radial direction between three and ten degrees. In another embodiment, pressure side seal slot 474 is angled relative to the reference axis in the radial direction from four to six degrees. In yet another embodiment, pressure side seal slot 474 is angled relative to the reference axis in the radial direction at five degrees, approximately five degrees, or within a predetermined tolerance of five degrees.

Pressure side sealing surface 495 spans along pressure side slash face 472 at an angle with the forward portion of pressure side sealing surface 495 being angled toward forward end 466 and in the direction that blade root 462 extends from platform 463, and with the aft portion of pressure side sealing surface 495 being angled toward aft end 467 and in the direction that airfoil 461 extends from platform 463.

Pressure side sealing surface 495 may be angled relative to the reference axis. Angle 87 also illustrates the angle of pressure side sealing surface 495 relative to the reference axis. Pressure side sealing surface 495 may be angled in the radial direction relative to the reference axis with the forward portion of pressure side sealing surface 495 being closer to the reference axis than the aft portion of pressure side sealing surface 495. In one embodiment, pressure side sealing surface 495 is angled relative to the reference axis in the radial direction between three and ten degrees. In another embodiment, pressure side sealing surface 495 is angled relative to the reference axis in the radial direction from four to six degrees. In yet another embodiment, pressure side sealing surface 495 is angled relative to the reference axis in the radial direction at five degrees, approximately five degrees, or within a predetermined tolerance of five degrees.

In the embodiment shown, pressure side sealing surface 495 is the radially outer portion of pressure side seal slot 474 relative to the reference axis.

Referring to FIG. 4, suction side seal slot 484 includes forward suction side slot 488, aft suction side slot 489, and suction side sealing surface 496. Forward suction side slot 488 extends into suction side platform 483 from suction side slash face 482 below the leading edge 458, adjacent to forward suction side damper buttress 486, and above forward suction side damper buttress 486. Forward suction side slot 488 includes forward suction side surface 443. Forward suction side surface 443 may have a planar or a rounded surface, and may round into the concave shape of forward suction side slot 488. Forward suction side surface 443 is situated forward of leading edge 458, opposite the direction of trailing edge 459, and axially forward of leading edge 458 when turbine blade 460 is installed onto turbine disk 422. Forward suction side slot 488 may have a concave shape and spans from suction side underplatform pocket 485 to forward suction side surface 443, beyond leading edge 458.

Aft suction side slot 489 extends into suction side platform 483 from suction side slash face 482 below the trailing edge 459, adjacent to aft suction side damper buttress 487, and above aft suction side damper buttress 487. Aft suction side slot 489 includes aft suction side surface 444. Aft suction side surface 444 is distal to leading edge 458 and is the end surface of suction side seal slot 484 farthest from leading edge 458. Aft suction side surface 444 may have a planar or a rounded surface, and may round into the concave shape of aft suction side slot 489. Aft suction side slot 489 may have a concave shape and spans from suction side underplatform pocket 485 to aft suction side surface 444.

Suction side sealing surface 496 spans between forward suction side surface 443 to aft suction side surface 444, the length of suction side seal slot 484. Suction side sealing surface 496 may be a planar surface angling into suction side platform 483 from suction side slash face 482. Forward suction side slot 488 may include the forward portion of suction side sealing surface 496. Aft suction side slot 489 may include the aft portion of suction side sealing surface 496. The portion of suction side sealing surface 496 between forward suction side slot 488 and aft suction side slot 489 may angle into suction side platform 483 to suction side underplatform pocket 485.

Suction side seal slot 484 may span along suction side slash face 482 at an angle with forward suction side slot 488 angled toward forward end 466 and in the direction that blade root 462 extends from platform 463, and with aft suction side slot 489 angled toward aft end 467 and in the direction that airfoil 461 extends from platform 463. Suction side seal slot 484 may be angled relative to the reference axis.

Suction side seal slot 484 may be angled in the radial direction of the reference axis with forward suction side slot 488 being closer to the reference axis than aft suction side slot 489. Angle 88 is the angle of suction side seal slot 484 relative to the reference axis. Reference line 85 is shown to illustrate angle 88. In one embodiment, suction side seal slot 484 is angled relative to the reference axis in the radial direction between three and ten degrees. In another embodiment, suction side seal slot 484 is angled relative to the reference axis in the radial direction from four to six degrees. In yet another embodiment, suction side seal slot 484 is angled relative to the reference axis in the radial direction at five degrees, approximately five degrees, or within a predetermined tolerance of five degrees. The angles of suction side seal slot 484 and of pressure side seal slot 474 in the radial direction relative to the reference axis of turbine disk 422 are equal or within a predetermined tolerance.

Suction side sealing surface 496 spans along suction side slash face 482 at an angle with the forward portion of suction side sealing surface 496 being angled toward forward end 466 and in the direction that blade root 462 extends from platform 463, and with the aft portion of suction side sealing surface 496 being angled toward aft end 467 and in the direction that airfoil 461 extends from platform 463. Suction side sealing surface 496 may be angled relative to the reference axis.

Suction side sealing surface 496 may be angled in the radial direction relative to the reference axis with the forward portion of suction side sealing surface 496 being closer to the reference axis than the aft portion of suction side sealing surface 496. Angle 88 also illustrates the angle of suction side sealing surface 496 relative to the reference axis. In one embodiment, suction side sealing surface 496 is angled relative to the reference axis in the radial direction between three and ten degrees. In another embodiment, suction side sealing surface 496 is angled relative to the reference axis in the radial direction from four to six degrees. In yet another embodiment, suction side sealing surface 496 is angled relative to the reference axis in the radial direction at five degrees, approximately five degrees, or within a predetermined tolerance of five degrees. The angles of suction side sealing surface 496 and of pressure side sealing surface 495 in the radial direction relative to the reference axis are equal or within a predetermined tolerance.

In the embodiment shown, suction side sealing surface 496 is the radially outer portion of suction side seal slot 484 relative to the reference axis.

FIG. 5 is a detailed view of the portion of the cross section view of FIG. 2 around pin seal 430. Referring to FIGS. 2 and 5, pressure side sealing surface 495 may extend from pressure side slash face 472 to pressure side underplatform surface 498.

Pressure side sealing surface 495 may be a planar surface angling into pressure side platform 473 from pressure side slash face 472. Pressure side sealing surface 495 may be angled from pressure side slash face 472 towards blade root 462 in the direction opposite the direction that pressure side platform 473 extends and in the same direction that blade root 462 extends. Suction side sealing surface 496 may be a planar surface angling into suction side platform 483 from suction side slash face 482. Suction side sealing surface 496 may be angled from suction side slash face 482 towards blade root 462 in the direction opposite the direction that suction side platform 483 extends and in the same direction that blade root 462 extends.

Pressure side sealing surface 495 and suction side sealing surface 496 form a roof at the top of seal slot 464. Angle 83 is the angle between pressure side sealing surface 495 and suction side sealing surface 496. In one embodiment, the angle 83 between pressure side sealing surface 495 and suction side sealing surface 496 is between ninety-five degrees and one-hundred fifteen degrees. In another embodiment, the angle 83 between pressure side sealing surface 495 and suction side sealing surface 496 is between one-hundred degrees and one-hundred ten degrees. In yet another embodiment, the angle 83 between pressure side sealing surface 495 and suction side sealing surface 496 is one-hundred five degrees or approximately one-hundred five degrees.

Pressure side sealing surface 495 and suction side sealing surface 496 may each be angled relative to a reference plane 86. The reference plane 86 is the center plane and may be the plane of symmetry extending through blade root 462. The reference plane 86 may also extend from and include the stacking axis of turbine blade 460. The reference plane 86 extends through blade root 462 from forward end 466 to aft end 467. When turbine blade 460 is installed onto turbine disk 422, the reference plane 86 is a radial plane that includes the axis of turbine disk 422 and extends from the axis through the blade root 462.

Angle 81 is the angle that pressure side sealing surface 495 is angled relative to reference plane 86. In one embodiment, pressure side sealing surface 495 is angled relative to the reference plane 86 between sixty and seventy degrees. In another embodiment, pressure side sealing surface 495 is angled relative to the reference plane 86 from sixty-four to sixty-six degrees. In yet another embodiment, pressure side sealing surface 495 is angled relative to the reference plane 86 at sixty-five degrees, at approximately sixty-five degrees or within a predetermined tolerance of sixty-five degrees.

Suction side sealing surface 496 may be angled relative to the reference plane 86 in the opposite direction of pressure side sealing surface 495. Angle 82 is the angle that suction side sealing surface 496 is angled relative to reference plane 86. In one embodiment, suction side sealing surface 496 is angled relative to the reference plane 86 between forty and fifty degrees. In another embodiment, suction side sealing surface 496 is angled relative to the reference plane 86 from forty-four to forty-six degrees. In yet another embodiment, suction side sealing surface 496 is angled relative to the reference plane 86 at forty-five degrees, at approximately forty-five degrees or within a predetermined tolerance of forty-five degrees.

During operation of gas turbine engine 100, pin seal 430 is located adjacent to and configured to contact pressure side sealing surface 495 and suction side sealing surface 496 as illustrated in FIGS. 2 and 5. In some embodiments, pin seal 430 is angled between three and ten degrees in the radial direction relative to center axis 95 during operation of gas turbine engine 100. In other embodiments, pin seal 430 is angled from four to six degrees in the radial direction relative to center axis 95 during operation of gas turbine engine 100.

When the gas turbine engine 100 is not in operation seal slot 464 retains pin seal 430. The concave surfaces of forward suction side slot 488 (not shown in FIGS. 2 and 5) and aft suction side slot 489 are configured to include a storage cavity 490 to retain pin seal 430. In some embodiments, pin seal 430 does not extend beyond suction side slash face 482 when pin seal 430 is retained by storage cavity 490.

The concave surfaces of forward pressure side slot 478 (not shown in FIGS. 2 and 5) and aft pressure side slot 479 are configured to direct pin seal 430 into the roof formed by pressure side sealing surface 495 and suction side sealing surface 496 as centrifugal force overcomes gravity and to direct pin seal 430 to storage cavity 490 as gravity overcomes centrifugal force; forward suction side slot 488 and aft suction side slot 489 are similarly configured.

FIG. 6 is a plan view of the pin seal 430 of FIGS. 2 and 5. Referring to FIG. 6, pin seal 430 includes a body 431, a first end 432, and a second end 433. Body 431 has a cylindrical shape extending from first end 432 to second end 433. Body 431 is generally a right circular cylinder. In the embodiment shown, first end 432 is a hemisphere or includes a hemispherical shape and second end 433 is a hemisphere or includes a hemispherical shape. First end 432 and second end 433 are at opposite ends of body 431. In other embodiments, first end 432 and second end 433 are circular bases at each end of body 431; the edges between body 431 and first end 432, and body 431 and second end 433 may be rounded.

Referring to FIG. 5, pin seal 430 is configured to be installed between two adjacent turbine blades 460 within the pressure side seal slot 474 and the suction side seal slot 484. The diameter of pin seal 430 is configured to be larger than slash face gap 497. In one embodiment, the diameter of pin seal 430 is from 2.362 mm (0.093 inches) to 2.464 mm (0.097 inches). In another embodiment, the diameter of pin seal 430 is 2.413 mm (0.095 inches) or within a predetermined tolerance of 2.413 mm (0.095 inches).

FIG. 7 is a perspective view of suction side 481 of a turbine blade assembly 455 including the turbine blade 460 of FIG. 4 and the pin seal 430 of FIG. 6. Prior to installing turbine blades 460 to turbine disk 422 as part of turbine disk assembly 420, a pin seal 430 is affixed to each turbine blade 460. In the embodiment illustrated, pin seal 430 is affixed to turbine blade 460 within suction side seal slot 484 to accommodate installing turbine blade 460 axially from the aft side of turbine disk 422. In other embodiments, the pin seal 430 may be affixed to seal slot 464 in either pressure side seal slot 474 or suction side seal slot 484. Pin seal 430 may be glued to a turbine blade 460 or affixed by other methods. Adhesives such as tape may also be used to affix pin seal 430 to turbine blade 460.

Pin seal 430 is configured to extend from forward suction side slot 488 to aft suction side slot 489. When pin seal 430 is in contact with forward suction side surface 443, pin seal 430 is configured to extend beyond aft suction damper surface 494 and into aft suction side slot 489, overlapping with aft suction side damper buttress 487. When pin seal 430 is in contact with aft suction side surface 444, pin seal 430 is configured to extend beyond forward suction damper surface 493 and into forward suction side slot 488, overlapping with forward suction side damper buttress 486. In some embodiments, pin seal 430 is also configured to extend beyond leading edge 458 in the axial direction of the reference axis when pin seal 430 is in contact with aft suction side surface 444. Reference line 89 illustrates the distance that pin seal 430 extends beyond leading edge 458. Reference line 91 extends outward from an end of pin seal 430 perpendicular to the reference axis. Reference line 92 intersects the forward most point of leading edge 458 and extends parallel to reference line 91. Reference line 89 extends between reference lines 91 and 92 and is perpendicular to reference lines 91 and 92. In one embodiment, pin seal 430 extends beyond the forward most point of leading edge 458 from 0.254 mm (0.010 inches) to 0.762 (0.030 inches). In another embodiment, pin seal 430 extends beyond leading edge 458 at a minimum of 0.508 mm (0.020 inches) when pin seal 430 is in contact with aft suction side surface 444.

In one embodiment, the length of pin seal 430 is from 42.037 mm (1.655 inches) to 42.291 mm (1.665 inches). In another embodiment the length of pin seal 430 is 42.164 mm (1.660 inches) or within a predetermined tolerance of 42.164 mm (1.660 inches).

Pin seal 430 may interact with pressure side seal slot 474, forward pressure side slot 478, aft pressure side slot 479, forward pressure side damper buttress 476, aft pressure side damper buttress 477, forward pressure side surface 441, aft pressure side surface 442, forward pressure damper surface 491, and aft pressure damper surface 492 in the same or a similar manner as pin seal 430 interacts with suction side seal slot 484, forward suction side slot 488, aft suction side slot 489, forward suction side damper buttress 486, aft suction side damper buttress 487, forward suction side surface 443, aft suction side surface 444, forward suction damper surface 493, and aft suction damper surface 494 as described above.

One or more of the above components (or their subcomponents) may be made from stainless steel and/or durable, high temperature materials known as “superalloys”. A superalloy, or high-performance alloy, is an alloy that exhibits excellent mechanical strength and creep resistance at high temperatures, good surface stability, and corrosion and oxidation resistance. Superalloys may include materials such as HASTELLOY, INCONEL, WASPALOY, RENE alloys, HAYNES alloys, INCOLOY, MP98T, TMS alloys, and CMSX single crystal alloys. In embodiments, pin seal 430 is made from HAYNES 25 and turbine disk 422 is made from WASPALOY.

INDUSTRIAL APPLICABILITY

Gas turbine engines may be suited for any number of industrial applications such as various aspects of the oil and gas industry (including transmission, gathering, storage, withdrawal, and lifting of oil and natural gas), the power generation industry, cogeneration, aerospace, and other transportation industries.

Referring to FIG. 1, a gas (typically air 10) enters the inlet 110 as a “working fluid”, and is compressed by the compressor 200. In the compressor 200, the working fluid is compressed in an annular flow path 115 by the series of compressor disk assemblies 220. In particular, the air 10 is compressed in numbered “stages”, the stages being associated with each compressor disk assembly 220. For example, “4th stage air” may be associated with the 4th compressor disk assembly 220 in the downstream or “aft” direction, going from the inlet 110 towards the exhaust 500). Likewise, each turbine disk assembly 420 may be associated with a numbered stage.

Once compressed air 10 leaves the compressor 200, it enters the combustor 300, where it is diffused and fuel is added. Air 10 and fuel are injected into the combustion chamber 390 via injector 350 and combusted. Energy is extracted from the combustion reaction via the turbine 400 by each stage of the series of turbine disk assemblies 420. Exhaust gas 90 may then be diffused in exhaust diffuser 520, collected and redirected. Exhaust gas 90 exits the system via an exhaust collector 550 and may be further processed (e.g., to reduce harmful emissions, and/or to recover heat from the exhaust gas 90).

Referring to FIGS. 1 and 2, air 10 is heated from the combustion reaction and is directed through turbine 400. Some of the heated air may pass through slash face gaps 497 between turbine blades 460. Air 10 passing through slash face gaps 497 may impinge on disk posts 424 and may impinge on dampers 425. The heated air 10 may also increase the temperature of the portions of the turbine blades 460 adjacent blade underplatform pockets 465, portions of disk posts 424, and portions of dampers 425.

Reducing the temperature of these components, may increase the creep life and may increase the service life of these components. Referring to FIGS. 2 and 5, a seal slot 464 with a pin seal 430 may be located at each slash face gap 497. During operation of gas turbine engine 100, centrifugal force may locate pin seal 430 against pressure side sealing surface 495 and suction side sealing surface 496 of adjacent turbine blades 460. Each pin seal 430 may prevent the heated air from passing through a slash face gap 497, may reduce the amount of heated air passing through a slash face gap 497, or may impede the flow of the heated air passing through slash face gap 497. Pin seals 430 may also redirect the heated air passing through slash face gaps 497, which may prevent the heated air from directly impinging disk posts 424 or dampers 425. Preventing or reducing the heated air passing through slash face gaps 497 as well as preventing direct impingement onto disk posts 424 and dampers 425 may reduce the operating temperatures of portions of the turbine blades 460, disk posts 424 and dampers 425.

Pin seal 430 may be configured to extend forward of leading edge 458 in the axial direction of the reference axis. Extending either first end 432 or second end 433 forward of leading edge 458 may block the flow path of the heated air as it enters the geometry of airfoil 461.

During operation of gas turbine engine 100 the relative positions of adjacent turbine blades 460 and pin seal 430 may shift. Binding may occur between pin seal 430 and the adjacent turbine blades 460 and pin seal 430 may become wedged between the adjacent turbine blades 460. Increasing the angles of pressure side sealing surface 495 and suction side sealing surface 496 relative to the reference plane 86 and relative to each other, such as the angles disclosed above, may prevent or reduce the possibility of binding. Increasing the angles of pressure side sealing surface 495 and suction side sealing surface 496 may also facilitate a uniform contact margin between pin seal 430 and both pressure side sealing surface 495 and suction side sealing surface 496. Increasing the angles of pressure side sealing surface 495 and suction side sealing surface 496 may help the contact load vector align with the centrifugal force load vector.

Angling pressure side sealing surface 495, suction side sealing surface 496, pressure side seal slot 474, and suction side seal slot 484 in the radial direction relative to the reference axis may facilitate the use of a longer pin seal 430. A longer pin seal 430 may increase the contact area between pin seal 430 and both pressure side sealing surface 495 and suction side sealing surface 496, which may increase the seal. A longer pin seal 430 may also reduce the centrifugal force contact loads and stress concentrations on the turbine blades 460.

Pin seal 430 does not remain affixed to turbine blade 460 during operation of gas turbine engine 100. Once gas turbine engine 100 begins to operate, the pin seal 430 centrifugal force load and the increase in temperature may break or melt the adhesive or glue, which may allow the pin seal 430 to move into the correct position adjacent and in contact with pressure side sealing surface 495 and suction side sealing surface 496.

The features in turbine blade 460 such as pressure side seal slot 474 and suction side seal slot 484 may be formed by an investment casting process that uses two or more casting block pull directions, such as compound pull casting. The features may also be formed by a machining process, such as electrical discharge machining, milling, or grinding.

The preceding detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. The described embodiments are not limited to use in conjunction with a particular type of gas turbine engine. Hence, although the present disclosure, for convenience of explanation, depicts and describes particular turbine blades and pin seals, it will be appreciated that the turbine blades and pin seals in accordance with this disclosure can be implemented in various other configurations, can be used with various other types of gas turbine engines, and can be used in other types of machines. Furthermore, there is no intention to be bound by any theory presented in the preceding background or detailed description. It is also understood that the illustrations may include exaggerated dimensions to better illustrate the referenced items shown, and are not consider limiting unless expressly stated as such. 

What is claimed is:
 1. A pin seal for a gas turbine engine with a turbine disk and a plurality of turbine blades, the pin seal comprising: a body having a cylindrical shape; a first end; and a second end, opposite and distal to the first end; wherein the pin seal is configured to be installed between two adjacent turbine blades within a pressure side seal slot that extends into a pressure side slash face of a first turbine blade and a suction side seal slot that extends into a suction side slash face of a second turbine blade, and the length of the pin seal is configured such that the pin seal extends forward of an airfoil leading edge of each adjacent turbine blade at least by 0.020 inches when the pin seal is in contact with either an aft pressure side surface located at an end of the pressure side seal slot distal to the leading edge of each airfoil or an aft suction side surface located at an end of the suction side seal slot distal to the leading edge of each airfoil, and wherein the pin seal is angled from three to ten degrees in a radial direction relative to an axis of the gas turbine engine during operation of the gas turbine engine.
 2. The pin seal of claim 1, wherein a length of the pin seal is from 1.655 inches to 1.665 inches.
 3. The pin seal of claim 1, wherein a diameter of the pin seal is from 0.093 inches to 0.097 inches.
 4. The pin seal of claim 1, wherein the diameter of the pin seal is configured to be larger than a slash face gap between the pressure side slash face and the suction side slash face of the adjacent turbine blades.
 5. The pin seal of claim 4, wherein the pin seal is configured to contact a pressure side sealing surface and a suction side sealing surface, the pressure side sealing surface extending into a platform of the turbine blade from the pressure side slash face and being angled between three and ten degrees relative to the axis of the gas turbine engine, and the suction side sealing surface extending into the platform from the suction side slash face and being angled between three and ten degrees relative to the axis of the gas turbine engine.
 6. A gas turbine engine including the pin seal of claim
 1. 7. A turbine blade assembly for a gas turbine engine having a turbine disk with an axis, the turbine blade assembly comprising: a turbine blade having an airfoil extending in a first direction, the airfoil having a leading edge, a trailing edge, a pressure side spanning between the leading edge and the trailing edge, and a suction side spanning between the leading edge and the trailing edge; a blade root extending in a second direction, opposite the first direction, and a platform located between the airfoil and the blade root, the platform having a forward end adjacent the leading edge, an aft end adjacent the trailing edge, a pressure side platform extending from the pressure side, the pressure side platform including a pressure side slash face distal to the pressure side, the pressure side slash face extending from the forward end to the aft end, and a pressure side seal slot extending into pressure side platform from pressure side slash face, the pressure side seal slot including a forward pressure side slot located adjacent the forward end spanning a forward portion of the pressure side slash face with a concave shape, and an aft pressure side slot located adjacent the aft end spanning an aft portion of the pressure side slash face with a concave shape, wherein the pressure side seal slot is angled between three and ten degrees in a radial direction relative to a reference axis located below the blade root, opposite the airfoil, the reference axis being coaxial to the axis of the turbine disk when the turbine blade is installed onto the turbine disk, the pressure side seal slot being angled with the forward pressure side slot being radially closer to the reference axis than the aft pressure side slot, and a suction side platform extending away from the suction side in a direction opposite the pressure side platform, the suction side platform including a suction side slash face distal to the suction side, the suction side slash face extending from the forward end to the aft end, and a suction side seal slot extending into suction side platform from the suction side slash face, the suction side seal slot including  a forward suction side slot located adjacent the forward end spanning a forward portion of the suction side slash face, and  an aft suction side slot located adjacent the aft end spanning an aft portion of the suction side slash face,  wherein the suction side seal slot is angled between three and ten degrees in the radial direction relative to the reference axis with the forward suction side slot being radially closer to the reference axis than the aft suction side slot; and a pin seal affixed to the turbine blade, the pin seal having a body including a cylindrical shape, a first end, and a second, opposite the first end.
 8. The turbine blade assembly of claim 7, wherein the pin seal is affixed to the turbine blade within the suction side seal slot.
 9. The turbine blade assembly of claim 8, wherein forward suction side slot includes a forward suction side surface and the aft suction side slot includes an aft suction side surface, the suction side seal slot extends between the forward suction side surface to the aft suction side surface, and the pin seal extends beyond the leading edge in the direction of the reference axis when the pin seal is in contact with the aft suction side surface.
 10. The turbine blade assembly of claim 9, wherein the pin seal extends beyond the leading edge at a minimum of 0.020 inches.
 11. The turbine blade assembly of claim 8, wherein the pin seal is glued to the turbine blade.
 12. The turbine blade assembly of claim 9, further comprising: a forward suction side damper buttress extending from the suction side platform adjacent the forward end and extending down adjacent the blade root, the forward suction side damper buttress including a forward suction damper surface; and an aft suction side damper buttress extending from the suction side platform adjacent the aft end and extending down adjacent the blade root, the aft suction side damper buttress including an aft suction damper surface, the aft suction damper surface faces towards the forward suction damper surface and the forward suction damper surface faces towards the aft suction damper surface; wherein the pin seal extends beyond the forward suction damper surface when in contact with the aft suction side surface and the pin seal extends beyond the aft suction damper surface when in contact with the forward suction side surface.
 13. The turbine blade assembly of claim 7, wherein the pin seal includes a length from 1.655 inches to 1.665 inches, and a diameter of from 0.093 inches to 0.097 inches.
 14. The turbine blade assembly of claim 13, wherein the pin seal includes a length within a predetermined tolerance of 1.660 inches and a diameter within a predetermined tolerance of 0.095 inches.
 15. The turbine blade assembly of claim 7, wherein the first end and the second end each include a hemispherical shape.
 16. A gas turbine engine including the turbine blade assembly of claim
 7. 17. A turbine disk assembly of a gas turbine engine, the turbine disk assembly comprising: a turbine disk with a cylindrical shape, the turbine disk having disk posts, each disk post extending radially outward from the cylindrical shape, with adjacent disk posts forming a turbine disk slot there between; a plurality of turbine blades, each blade having an airfoil extending radially outward relative to an axis through the cylindrical shape of the turbine disk, the axis including a forward direction and an aft direction, the airfoil including a leading edge, a trailing edge axially aft of the leading edge relative to the axis, a pressure side spanning between the leading edge and the trailing edge, and a suction side spanning between the leading edge and the trailing edge, a blade root extending radially inward relative to the axis, the blade root including the shape of the turbine disk slots, and a platform located between the airfoil and the blade root, the platform including a forward end, an aft end axially aft of the forward end, a pressure side platform extending from the pressure side in a first circumferential direction relative to the axis, the pressure side platform including a pressure side slash face distal to the pressure side, the pressure side slash face extending in a radial direction relative to the axis spanning from the forward end to the aft end, and a pressure side seal slot extending into pressure side platform from pressure side slash face, the pressure side seal slot being angled between three and ten degrees in the radial direction relative to the axis, and a suction side platform extending from the suction side in a first circumferential direction relative to the axis, the suction side platform including a suction side slash face distal to the suction side, the suction side slash face extending in the radial direction relative to the axis spanning from the forward end to the aft end, and a suction side seal slot extending into suction side platform from suction side slash face, the suction side seal slot being angled between three and ten degrees in the radial direction relative to the axis; and a plurality of pin seals, each pin seal having a body including a cylindrical shape, a first end, and a second end opposite the first end; wherein each pin seal is located within a seal slot formed from the pressure side seal slot and the suction side seal slot of adjacent turbine blades, each pin seal extending axially forward of the leading edge of each adjacent turbine blade.
 18. The turbine disk assembly of claim 17, wherein the pin seal extends axially forward of the leading edge of each adjacent turbine blade at a minimum of 0.020 inches.
 19. The turbine disk assembly of claim 17, wherein the pressure side seal slot is angled from four to six degrees in the radial direction relative to the axis, and the suction side seal slot is angled from four to six degrees in the radial direction relative to the axis.
 20. A gas turbine engine including the turbine disk assembly of claim
 17. 